Oral irrigator



FIG. 1 is a front perspective view of an oral irrigator, showing my new design;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a right side view thereof;

FIG. 5 is a left side view thereof;

FIG. 6 is a bottom view thereof; and,

FIG. 7 is a top view thereof.

The broken lines shown in the drawings illustrate portions of the article and form no part of the claimed design. 

CLAIM The ornamental design for an oral irrigator, as shown and described. 